An investigation of training transfer from strength and conditioning to athletic performance using large-scale evidence synthesis and real-world data.

Murphy, Andrew Neil

Abstract

Over the past 50 years, strength and conditioning (S&C) has experienced substantial growth, leading to a rapid expansion of research that has culminated in an extensive literature base seeking to refine S&C prescription. High-quality evidence synthesis summarises and assists researchers and practitioners to navigate the over-whelming amount of research that is now available. High-quality evidence synthesis can also develop novel insights for more effective decision making. The aims of this thesis were to: 1) conduct large-scale evidence synthesis work and explore how S&C research could be summarised and presented to explain what magnitude of adaptations are expected following interventions; 2) through evidence synthesis work investigate influential factors to optimise prescription 3) conduct a meaningful primary investigation that addresses the key research gaps identified through the evidence synthesis work, while maintaining a focus on the factors that influence physical performance adaptations in athletes. This first aim was achieved through conducting the largest synthesis of longitudinal S&C research, including data from 643 studies (Chapter 3). The results defined novel context-specific effect size (ES) thresholds for S&C outcomes of strength, power, jumping and sprinting performance, that researchers and practitioners can incorporate for accurate interpretation and communication of the magnitude of change following S&C training. An accessible Bayesian updating tool was developed, integrating the newly defined ES thresholds as informative priors for better analysis of S&C data. Sub-analyses of the influence of training specificity identified increases of ~0.17 with specific training and outcome couplings. The second aim was achieved through two high quality meta-analyses (Chapters 4 and 5). In Chapter 4, the dose-response relationships between resistance-dominant interventions and similar outcomes were modelled, identifying variables of intervention duration and training intensity to be most important in improving performance across outcomes. The findings also highlighted different intensity (% 1RM) profiles required for maximising effects across outcomes. In Chapter 5, the effects of non-sprint specific and sprint-specific training on sprinting performance were compared in team sport athletes. The results identified greater overall improvements to sprinting performance than found in the larger meta-analyses in the previous chapters, but also found evidence of greater improvements with higher intensity training (>80% 1RM) and over longer durations (>8 weeks). Furthermore, the analysis examined the transference of improvements across outcomes, concluding one standard deviation improvements in strength, power or jumping translates to 0.5-0.8 standard deviation increases in sprinting performance. The large-scale meta-analyses consistently highlighted a lack of research conducted with highly-trained athletes over prolonged durations. To address this research gap, retrospective physical performance data were collected from two professional sports teams to explore the within and across season changes of athletes conducting S&C training in the field (Chapter 6). A comprehensive analysis found limited systematic changes and that any improvements may be dependent on baseline capacity, emphasising the requirement for individualised S&C training. Examination of within-athlete variation outlined increases in variability throughout competitive season, with implications for long-term athlete monitoring. Overall, the thesis presents a range of novel findings, employing large-scale evidence synthesis to summarise the effectiveness of S&C training and investigate moderating factors to optimise prescription and maximise improvements across multiple common outcomes. Finally, a primary investigation was conducted exploring the long-term physical performance changes in professional athletes to address limitations of current S&C research.

Citation

MURPHY, A.N. 2025. An investigation of training transfer from strength and conditioning to athletic performance using large-scale evidence synthesis and real-world data. Robert Gordon University, PhD thesis. Hosted on OpenAIR [online]. Available from: https://doi.org/10.48526/rgu-wt-2989520

• Thesis Type: Thesis
• Deposit Date: Aug 29, 2025
• Publicly Available Date: Aug 29, 2025
• DOI: https://doi.org/10.48526/rgu-wt-2989520
• Keywords: Strength and conditioning; Physical performance; Evidence synthesis; Meta-analysis; Effect size
• Public URL: https://rgu-repository.worktribe.com/output/2989520
• Award Date: Apr 30, 2025